Today, we're given a lemon, and we make lemonade. The
University of Houston's College of Engineering presents this series about the
machines that make our civilization run, and the people whose ingenuity created them.

Any kid interested in airplanes in 1940 looked at the new
Bell P-39 Airacobra in awe. It was pure streamlined menace. Its
liquid-cooled engine was mounted behind the pilot, and its nose tapered into a
37-mm canon in the propeller hub. As we soaked up propaganda about American air
superiority, we saw it everywhere.

America eventually achieved air superiority, but not through the P-39. No sooner
did the experimental version reach the Army Air Corps, than they began modifying it.
They thought the air-scoop imposed too much drag. They reduced the scoop, and
changed over to a simple mechanical supercharger.

That backed up the center of gravity and made the plane hard to fly. They reduced
the wingspan by two feet. When they were done, the Airacobra simply couldn't
compete above 10,000 feet, which is where much of the air war was being waged. The
British refused to use it; American pilots called it the Iron Dog.

We'd created our lemon. For us at home, it continued to be a glamorous icon of American
air power. It was wall-paper for cigarette ads and War Bond sales. And the actual
airplane was being produced in vast numbers. But no lemonade, at least not yet.

One country saw value in it -- the Soviet Union. So we sent P-39s to Iran and Fairbanks,
Alaska, then flew them into the Soviet Union. Great Britain also sent hers off to
Russia. In all, Russia received 5000 Airacobras. But why did they want them?

Russia had begun the war with antediluvian Polikarpov biplane
fighters. Their designs continued to lag behind the west until late in the war when
their Yak and Lavochkin fighters finally emerged as competitive pursuit planes. But
pursuing bombers was not so important by then. Germany's bombing capacity had been
seriously spent over Great Britain in 1940. She was in no position to go after the
distant cities of the Soviet Union.

Germany's war with Russia was being fought on the vast expanse of Russia's western lands.
And down there, nearer to the hard earth, the P-39 became Russia's lemonade. As a low
level attack plane -- an anti-tank gun platform -- it was very effective. Then, with
tanks out of the way, P-39s went after ground troops.

My fascination with the P-39 is less a fascination with an airplane, for it was surely
one of the less memorable flying machines. Rather it is with the old myth that war
drives invention. What war drives, besides production, is adaptation. It gets in the
way of invention because everything moves too fast. Necessity is the mother of quick
response.

In a less urgent world, post-production tinkering might've made a fine airplane of the
P-39, but that was not to be. War created a kludge which was then turned into useful
lemonade by resourceful fliers fighting for theirs and their country's very life.

I'm John Lienhard, at the University of Houston,
where we're interested in the way inventive minds
work.

Cards such as these appeared in cigarette cartons ca. 1940 -- one more means for
attracting kids to smoking. This one doesn't show the air-scoop behind the pilot,
cannon in the nose, or engine exhaust pipes. It anticipates a 400 mph speed
which was about 30 mph slower than the last versions of the air-plane. And it calls
it a high-altitude interceptor, when it functioned effectively only at low altitude.